Mathigon
Mathigon: Math Foundations: Grades 6 8
This is the electronic text for math foundations for grades 6-8. It is in the process of being rewritten so only specific sections are available now. More will be added over time.
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Mathpower: Math Anxiety Self Test
Do you think you (or your students) might suffer from math anxiety? Taking this quick self test may help you answer the question.